Professor of Chemistry, Brooklyn College of CUNY
BS California State University, Chico; Ph.D. Chemistry, U. Wyoming
Our group utilizes both experimental and theoretical methods to research fundamental aspects of organic chemistry and photochemistry. We are eager to accept researchers from various backgrounds, including nanotechnology, biochemistry, and even engineering. Our main focus is controlling and amplifying the production of reactive oxygen species. Our current projects involve organic oxidation mechanisms, visible-light photosensitization, secondary photosensitization, latent reactions following photooxidation, and photochemical-device development. One research area involves the use of fiber optics combined with sensitizer drugs for the production and precise delivery of singlet oxygen to eradicate cancer cells. This technique is referred to as “point-source” photodynamic therapy (i.e., PSPDT), delivers oxygen and red diode laser light through a device tip directed at the tumor site. This device helps avoid damage to healthy cells by focusing the sensitizer drugs and laser light within the tumor site. We also study the interfacial behavior of reactive oxygen species, including radicals at nanoparticle interfaces, and also the delivery of alkoxy radicals and singlet oxygen both as individual or tandem disinfectants. As mentioned above, secondary reactions are of interest to us. For example, the deconvolution of competitive light and dark processes is us offering insight into a priming mechanisms, including singlet oxygen priming as distinct from photodynamic priming. We are also using density functional theory and ab initio calculations which guide and deepen our understanding of experiments. Our work is currently funded by the National Science Foundation.
C. C. Tonon; Xu, Q.; Ghosh, G.; S Ashraf; A. Nara de Sousa Rastelli; T. Hasan; A. Greer; A. L. Lyons “Evaluation of Photosensitizer-Containing Superhydrophobic Surfaces for the Antibacterial Treatment of Periodontal Biofilms” J. Photochem. Photobiol. B 2022, 112458.
B. Malek; W. Lu; P. P. Mohapatra; N. Walalawela(a); S. Jabeen(a); J. Liu; A. Greer “Probing the Transition State-to-Intermediate Continuum: Mechanistic Distinction Between a Dry vs Wet Perepoxide in the Singlet Oxygen ‘Ene’ Reaction at the Air-Water Interface” Langmuir 2022, 38, 6036-6048.
E. M. Greer; V. Siev; A. Segal; A. Greer; C. Doubleday “Computational Evidence for Tunneling and a Hidden Intermediate in the Biosynthesis of Tetrahydrocannabinol” J. Am. Chem. Soc. 2022, 144, 7646-7656.
Belh, S. J.(a); Ghosh, G.; Greer, A. “Surface-Radical Mobility Test by a Self-Sorting Mechanism: Symmetrical Product upon Recombination (SPR)” J. Phys. Chem. B 2021, 125, 4212-4220.
A. M. Durantini; A. Greer “Interparticle Delivery and Detection of Volatile Singlet Oxygen at Air/solid Interfaces” Environ. Sci. Technol. 2021, 55, 3559-3567.
R. M. O’Connor(c); A. Greer “How Tryptophan Oxidation Arises by ‘Dark’ Photoreactions from Chemiexcited Triplet Acetone” Photochem. Photobiol. 2021, 97, 456-459.
A. M. Durantini; P. P. Mohapatra; M. Ashaque(c); M. E. Zatoulovski(c); M. M. Kim; K. A. Cengel; T. M. Busch; T. C. Zhu; A. Greer “Photooxidative Vulnerability to Intralipid in Photodynamic Therapy” In Periodical Reports in Photochemistry of the Royal Society of Chemistry; Protti, S.; Raviola, C. Eds.; Cambridge, UK 2021, Vol. 48, pp. 411-422.
M. J. Sosa; M. N. Urrutia; P. L. Schilardi; M. I. Quindt; S. Bonesi; D. Denburg; M. Vignoni; A. Greer;E. M. Greer; A. H. Thomas “Mono– and Bis-Alkylated Lumazine Sensitizers: Synthetic, Molecular Orbital Theory, Nucleophilic Index, and Photochemical Studies” Photochem. Photobiol. 2021, 97, 80-90.
J. Robinson-Duggon; N. Pizarro; G. Gunther; D. Zúñiga-Núñez; A. M. Edwards; A. Greer; D. Fuentealba “Fatty Acid Conjugates of Toluidine Blue O as Amphiphilic Photosensitizers: Synthesis, Solubility, Photophysics, and Photochemical Properties” Photochem. Photobiol. 2021, 97, 71-79.
Matikonda, S. S.; Helmerich, D. A.; Meub, M.; Beliu, G.; Kollmannsberger, P.; Greer, A.; Sauer, M.; Schnermann, M. J. “Defining the Basis of Cyanine Phototruncation Enables a New Approach to Single Molecule Localization Microscopy” ACS Cent. Sci. 2021, 7, 1144-1155. Highlighted in C&E News.
M. S. Oliveira; G. Chorociejus; J. P. F. Angeli; G. M. V. V. Safadi; G. L. B. Aquino; G. E. Ronstein; L. F. Barbosa; M. C. Oliveira; M. H. G. Medeiros; A. Greer; P. Di Mascio “Heck Reaction Synthesis of Anthracene and Naphthalene Derivatives as Traps and Clean Chemical Sources of Singlet Molecular Oxygen in Biological Systems” Photochem. Photobiol. Sci. 2020, 19, 1590-1602.
O. Turque(a); A. Greer; O. R. Wauchope “Synthetic Feasibility of Oxygen-driven Photoisomerizations of Alkenes and Polyenes” Org. Biomol. Chem. 2020, 18, 9181-9190.
S. Jabeen(a); M. Farag(c); B. Malek(b); R. Choudhury; A. Greer A Singlet Oxygen Priming Mechanism: Disentangling of Photooxidative and Downstream Dark Effects. J. Org. Chem. 2020, 85, 12505-12513.
Ortel; S. Jabeen; A. Greer “Adjuvants that Empower the Action of Photodynamic Therapy” Photochem. Photobiol.2020, 96, 725-727.
Belh, S. J.; Walalawela, N.; Lekhtman,; Greer, A. “Dark-binding Process Relevant to Preventing Photooxidative Damage: Conformation Dependent Light and Dark Mechanisms by a Dual-functioning Diketone” ACS Omega 2019, 4, 22623-22631.
Walalawela; A. Greer “Heterogeneous Photocatalytic Deperoxidation with UV and Visible Light” J. Phys. Org. Chem.2018, e3807.
Malek; W. Fang; I. Abramova; N. Walalawela; A. A. Ghogare; A. Greer “Ene Reactions of Singlet Oxygen at the Air-Water Interface” J. Org. Chem. 2016, 81, 6395-6401.
A. Ghogare; A. Greer “Using Singlet Oxygen to Synthesize Natural Products and Drugs” Chem. Rev. 2016, 116, 9994-10034.
[(a) Ph.D. student; (b) MS student; (c) undergraduate student; (d) research assistant at Brooklyn College]
Lyons, A.M.; Greer, A.; Xu, Q.F., Singlet Oxygen Generating Device for Selective Destruction of Pathogens, US patent application No. 15/729005 Publication No. 20180099063, published 4/12/2018.
External Federal Funding
NSF Single Investigator Award, 2022-2025
Mechanistic Organic Photochemistry: Dark Processes and Toxicity Priming
NSF STTR Phase I Award, 2021-2022, (for our company SingletO2 Therapeutics LLC with co-PI Marc Hodes, Tufts University)
Safe Disinfection and Oxygen-Level Enrichment in Recirculating Aquaculture Systems (RAS) Using Singlet Oxygen
NSF Single Investigator Award, 2019-2022,
Multiphase-Separation and Control of Serially Produced Reactive Oxygen
NIH SBIR Phase II Award, 2019-2022, (for our company SingletO2 Therapeutics LLC)
3D-Printed Superhydrophobic-Tipped Optical Fiber for Targeted Periodontal Photodynamic Therapy